Question: Which monoanion should I use to make conjugate acid of citric acid?
Paraphrase: Which monoanion ought to I utilize to create conjugate corrosive of citric acid?
SPARQL (Wikidata):  select distinct ?sbj where { ?sbj wdt:P4147 wd:Q159683 . ?sbj wdt:P31 wd:Q55523986 }